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main reference

hallucinogenic principles contained in certain mushrooms (notably two Mexican species,
Psilocybe mexicana and
Psilocybe cubensis [formerly
Stropharia cubensis]). Hallucinogenic mushrooms used in religious ceremonies by the Indians of Mexico were considered sacred and were called “god’s flesh” by the Aztecs. In the 1950s the active principles psilocin...

drug use and abuse

...purpurea), a fungus on rye and wheat, (2) mescaline, the active principle of the peyote cactus (
Lophophora williamsii), which grows in the southwestern United States and Mexico, and (3)
psilocybin and psilocin, which come from Mexican mushrooms (notably
Psilocybe mexicana and
Stropharia cubensis). Bufotenine, originally isolated from the skin of toads, is the alleged...

...are used by cultists among the Indians in Latin America, especially in the state of Oaxaca in southern Mexico. The chief species is
Psilocybe mexicana, of which the active principle is
psilocybin and its derivative psilocin, in their chemical composition and activity not unlike LSD (
D-lysergic acid diethylamide); the latter is synthesized from the alkaloids...

hallucinogenics

...purpurea), a fungus on rye and wheat; mescaline, the active principle of the peyote cactus (
Lophophora williamsii), which grows in the southwestern United States and Mexico; and
psilocybin and psilocin, which come from certain mushrooms (notably two Mexican species,
Psilocybe mexicana and
Stropharia cubensis). Other hallucinogens include bufotenine, originally...

...the orderly input of information and “jamming the circuits.” Many botanically derived hallucinogens seem to function this way—e.g., LSD and the ergot (a fungus) that grows on rye,
psilocybin from mushrooms, mescaline from the peyote cactus, and tetrahydrocannabinol (THC) from marijuana. Hallucinations also can be induced by input overload produced mechanically, such as...

Hofmann

...methergine, a drug used to treat postpartum hemorrhaging, from ergot. However, most of his later research focused on the psychotropic qualities of various plants and fungi. In 1958 he synthesized
psilocybin and psilocin, the hallucinogenic compounds in the mushroom
Psilocybe mexicana, having been sent samples by an amateur mycologist intrigued by his work with LSD. In 1960 he...

Leary

At Harvard Leary began experimenting with
psilocybin, a synthesized form of the hallucinogenic agent found in certain mushrooms. He concluded that psychedelic drugs could be effective in transforming personality and expanding human consciousness. Along with psychologist Richard Alpert (later Ram Dass), he formed the Harvard Psilocybin Project and began administering
psilocybin to graduate...